Pneumatic rock-drill.



T. J.'BARBRE. PNEUMATIC ROCK DRILL.

APPLICATION FILED MAR. 22, 1912.

Patented Apr. 7, 191i 2 SHEETS-SHEET 2.

LVVENTOR. Thdrrzms J. Bwl'orzz T. J. BARBRE.

PNEUMATIC ROCK DRILL.

I APPLICATION FILED MAR. 22, 1912. 092,237 Patented Apr. 7, 1914.

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IV/TNESSES- THOMAS J. BARBRE, 0F DENVER, COLORADO.

PNEUMATIC ROCK-DRILL.

Specification of Letters Patent.

Patented Apr. 7, idle.

Application filed March 22, 1912. Serial No. 685,486.

To all whom it may concern:

Be it known that I, THOMAS J. BARBRE, a citizen of the United States, residing in the city and county of Denver and State of Colorado, have invented certain new and useful Improvements in Pneumatic Rock-Drills; and I do declare the following to be a full, clear, and exact description of my invention, such as will enable others skilled in the art to which it appertains to make and usethe same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

My invention relates to improvements in pneumatic rock drills and has for its ob ectthe provision of a device of this character,

whose parts are simple and inexpensive in manufacture.

Another object of my invention is to provide a simple and effective valve for controlling the inductlon of the motive fluid al-' ternately to the front and rear of the piston.

Another object of my invention is .to provide simple and efi'ectivemeans for supplying lubricant to the various parts of the rock drill.

Still another object of my invention resides in the provision of a rock drill whose arts are positive in operation.

- VViththese and other ob ects in view, I

will proceed to describe my invention with.

reference to the accompanying drawings forming a part hereof.

In the drawingst-Figure 1 is a longitudinal section of my improved rock drill, showing the valve applied to the motor. Fig. 2 is a similar View, showing thevalve in a different rel five position. Fig. 3 is a plan view of my improved rock drill, showing thepartsin their assembled relation.

Fig. 4 is a sectional detail view of a valve employed for controlling the motive fluid to the motor and feed cylinder. This valve also serves to admit lubricant to the drill.

Fig. 5 is a similar view, showing the valve in a different relative position. Fig. 6 isa longitudinal section of the valve for controlling the induction of the motive fluid to the front and rear of the piston. of the valve piece employed for controlling the motive fluid supply.

The same reference characters represent the same parts in all the views.

Referring, first, to Fig. 3, let the numeral 5 designate the feed cylinder of my \im said valve piece,

Fig. 7 is a plan View proved rock drill and the numeral 6 tor thereof. The feed cylinder 5 and the motor 6 are connected together, in operative relation, by means of rods or bolts 7 passed through ears 8 and9, respectively formed on the motor and feed cylinder. interposed between the motor and feed cylinder, I arrange a valve housing, designated in its entirety, by the reference character 10. See

Figs. 1 and 2. This valve housing is proyided with a centrally located opening 12, in which I arrange a reciprocal valve piece 13. This valve piece 13 is known as the spool and while it may be old to employ a spool type valve, in a rock drill, for controlling the motive fluid to the drill, there are certain features of novelty embodied in the valve piece employed by me which accomplish effective and positive operation of the valv e piece. These novel features also obviate many delicate parts which have heretofore been employed in drills of this character and as a consequence influence the operation of the drill, for the better.

The operation of the valve piece 13, for controlling the induction of the motive fluid to the front and rear of the piston will be more clearly described and understood by reference to Figs. 1 and 2, in which figures the various ports and passages are illustrated. In Fig.1, I'ha-ve shown the position of the valve piece 13, from the feed pipe 14, to the rear of the piston 15, for the forcing of the said piston forwardly into engagement with a drill steel 16, which is arranged in the forward extremity of a cylinder 17 of the motor 6, while in Fig. 2, I have shown the position of the valve piece 13 to admit motive fluid forward of the piston l6,'for forcing the said piston rear- Wardly. These two positions of the valve piece 13 respectively admit the motive fluid rearwardly and forwardly of the piston 15 and by virtue of means, hereinafter described, for changing the position of the the motive fluid is alterrearwardly and forwardly whereby a constant reciprois maintained in nately admitted of the piston 15, cation of the compression the piston 17.

Before going into the operation of my improved drill, I wish to state this cap is provided with a passage 19, which leads from the. motive fluid supply pipe'l i. This cap 18 serves as a protection the me that the valve housing 10 is inclosed by;a cap 18, andthat to admit motive fluid 35 which leads through der l7 and communicates with the interior for the valve housing 10 and the valve piece 13 and also serves as a artition or means of separating the feed. cylinder 5 from the motor 6. Now.assumin that the valve piece 13 is in the position llustrated iri Fig. 1, and that the motive fluid has been turned on by means of a valve '20, the (ionstruction of which will be hereinafter explained, the motive fluid enters through the passage 19, formed in the cap 18, and thence through the passage21, formed in the valve a housing 10, and registering with the passa e piece 13,'through a port 24, and moves the valve piece to the position indicated in Fig. 2, whereupon themotive fluid, from the passage 19, will pass through perforations 25 formedin the flange 26 of the valve piece 13, to the interior, or hollow 27 thereof, and from the hollow 27 through perforations 28, formed in a'shoulder 29 of the valve piece 13, into a circumferential pas-- sage 30 formed in the valve housing 10. From this circumferential passage 30, the live motive fluid will pass through a port 31, to a longitudinally disposed passage. 32,"

the wall of the cylinof the cylinder 17, near. the forward ex; tremity of the. latter through a' port 33. Thus the .livemotive fluid enters the cylinder'l7 forwardly of the piston 15 and forces the latter rearwardly. As the piston 15 is moving rearwardly, the air in the rear of the piston will exhaust through a port 34 into a passage 35 and thence through a port 36 and a circumferential groove 37 formed in the valve housing surroundin the opening 12 in the latter. The valveis provided with a passage 38 which communicates with the atmosphere, through the cap-18, as shownlat 39. Consequently when the exhaust h v fntered the oiig'ening 12 between the shou' ers, or flangifij 2 6 and 29, of the valve piece 13, it will pass through this passage'38 ever, as soon as the piston 15 has moved rearwardly far enough to coverthe port 34, the exhaust will be cut 'ofl" and the piston will then compress the motive fluid be tween the' iston and the rear end of the cylinder and this coinpression will normally act upon the valve. piece 13 to shift th latter to the rlf for any reason this compression does not ousing 10 to the atmosphere. How-.

shift the valve piece 13, the piston 15 will strike a projection 40, formed on the inner extremity of the valve piece, to the position illustrated in thus bring about the condition first explained in connection with Fig. 1, ornin other words, will establish communication of the live motive fluid with the interior of the cylinder L7 in the rear of the piston 15.

From the foregoing described two positions of the valve piece 13, it will be readilv understood that this valve piece will be alternately establishing communication of the'live motive fluid'with the interior of the cylinder 17 in the rear and front of the piston 15, whereby this piston 15 is kept constantly reciprocating and on each for- 16, which forces the latter into the rock or other material in which the hole is being drilled. l I wish to call special attention to the construction of my val nated in the drawings by the reference character 13. This valve piece is hollow and the induction of the live motive fluid to the interio'r ofthe cylinder 17, forwardly of the of this valve piece. B shaped valve employe the frictional con-- 'tactof the valve piece,

with the housing 10,

13. In other words, when the induction of induction. passages into contact with the valve piece 13, it is distributed evenly erting all ofwits pressure or force on the valve piece 13 at one particular point.

I will now proceed to describe the means .for controllingthe induction of the motive fluid to the feed cylinder 5 and themotor 6. To the cap 18, I connect a valve housing 41, into which the supply pipe 14 leads. In this 'housin 41,thevalve 20 is arranged and it is by'vntue of this valve 20 that the induction of the livemotive fluid, to the'feed cyl-, inder-5 and the motor 6, is controlled. Conoperating member 42, which is hollow and is adapted to contain a supply of lubricant introduced thereto through a port or opening 43, which is closed by a screw plug 54. The valve'g2O is constructed so as to introduce a position illustrated in Fig. 1, but

ward stroke strikes the-tappet, or drill steel.

is reduced to a minimum and goes far to- F ig. 1, which will alternately shifted to the two positions for ve piece, which is desigpiston 15, is established through the hollow virtue of the spoolthe motive fluid passes out of the various around'the said valve piece insteadof ex-.

nected' with this housing ,41, is a handle or limited amount of the lubricant through the :induction passage 19 into the motor, when- I motor.

turning of the valve piece through the opening 17 .60

. tion, indicated aoeaaev ever the valve piece is turned to establish communication of the motive fluid with the In Fig. 1 l have illustrated. a detailed view of the valve 20, and the housing 11 and in this view, the valve piece 20 is shown in position to cut off the motive fluid from bot-h the feed cylinder 5 and the motor 6, however, the valve piece 20 is provided with a recess 44 formed therein and which is in communication with the interior of the handle 12, through a port 15, when the valve piece 20 is in the position, to cut ofl the motive fluid from the feed cylinder 5 and the motor 6. Now assuming that it is desired to start the rock drill in operation, the handle 46 of the valve piece 20, is turned to the dotted line position indicated in Fig. 5, whereby an opening piece 20, is brought into communication with a passage 48, leading to the feed cylinder 53 through the cap 18. When the valve piece 20 isin this position the live motive fluid will pass from the supply pipe 14, through a passa e 19 formed in the housing 41, and a passage 50, formed in the valve piece thence through the passage 17 of the valve piece and passage 18, of the cap 18, to the interior of the feed cylinder 5,whereby the drill is caused to move into engagement with the rock or material to be drilled, by virtue of the fact that the compression of the mo,- tive fluid in the feed cylinder 5 will cause the said cylinder to move on a piston 51. It is understood that-this piston 51 is normally engaged with a support or the ground opposite to the point where the hole is to be drilled and consequently the rock drill is constantly moved toward the material in which the hole is being drilled. Now as soon as the communication of the live motive fluid has been established with the 5, in the manner above described, a further 20 will result in bringing an opening 52, formed in the valve piece 20, into communication with the passage 19 leading to the motor. When the valve piece 20 has been thus turned so that its opening 52 communicates with the induction passage 19, the motive fluid 'will pass from the supply pipe 14, through the passage 19, of the housing 11, opening 50, of the valve piece 20 and opening 52,, of the said valve piece and thence through the induction passage 19 in the manner heretofore dethat the comscribed. At the same time municatiou of the motive fluid 1s estabhshed with the motor, induction of the motive flui is also established with of the valve piece and passage 48 of the cap 18. When the valve piec e,20 has been turned to the posiin Fig. 5, the recess 44 has also been brought into commun cation w1th a recess 53, formed in the housmg 17 formed in the valve feed cylinder of the motive fluid, the feed cylinder flange is arranged cent the valve sleeve and communicating with the induction passage 19, whereby the oil or lubricant, which is passed from .the hollow handle 12, into this recess'ti, through the port 45, when the position shown in Fig. 4t, will now pass from this recess 44:, by gravity, and the recess 53 into the induction passage 19 and will be carried into the motor with the induction of the live motive fluid thereto.

Of course, it is necessary before the motive fluid is turned into the motor and this is accomplished by establishing communication of the motive fluid with the feed cylinder before establishing c0mmuni-' cation of the motive fluid with the motor, in the manner above described.

Attention is here called to the fact that 1 form a relatively small passage 55, in the flange 29 of the valve piece 13, whereby the motive fluid, which has passed to the rear of the valve piece for forcing the latter forwardly, is permitted to leak out through the passage 55, between the two flanges 29 and 26 and out through the passage 38 to'the atmosphere while the valve piece'13 is moving rearwardly under the influence of the motive fluid in the cylinder 17 to set the drill in the rear of the piston 15. Thus as soon as the compression takes place in the-cylinder in the rear of the piston 15, the valve iece 13 will be freely moved rearwardly un ,er the influence of the compression for establishing communication of the motive fluid withthe forward extremity of the cylinder 17 in front of the piston.

Attention is here called to the fact that as the piston 15 moves forwardly the air in the cylinder 17 in front of the said piston will exhaust through the port 38, passage 32 and port 31, into the opening 12 and out through the passage 38 to the atmosphere.- While I have described and illustrated herein a specific form of my invention, it must be understood that 1 am not limited thereto and that the same may and varied without departing from the spirit of my invention andthe domain of the appended claim. I

Having thus described my invention, what I claim is 2- In a pneumatic tool, a cylinder, a iston reciprocably mounted in said cylin er, a

valve housing, a shoulder formed in said valve housing, a valve piece mounted in said valve housing for controlling the induction said valve piece consisting of a hollow member having an annular flange at each extremity, one of said flanges being arranged to close off the induction of.

the motive to the rear of he piston when the valve piece is in oneposition, while the other to establish communication of the motiye fluid with the cylinder in u 7 front of the piston, the last named flan e from therear of said valve piece when the adapted to rest upon said shoulder of said latter moves re'arwardly. valve housing while said valve "iece is in In testimony whereof I aflix my signature position to establish communication of the in the presence of two witnesses.

motive fluid with the cylinder in front of THOMAS J. BARBRE. the piston, and said last named flan e hav- Witnesses: ing'a relatively small opening theret rough JNO. .G. POWELL,

adapted to permit the motive fluid to escape FELIX THms. 

